Hearing aid device and a method of manufacturing a hearing aid device

ABSTRACT

A hearing aid device and a method of manufacturing the hearing aid device provide a housing and a first conductive layer. The housing has a first non-conductive layer and a second non-conductive layer. The first conductive layer is disposed between the first non-conductive layer and the second non-conductive layer.

FIELD OF THE INVENTION

The present invention relates to a hearing aid device and a method formanufacturing the hearing aid device.

BACKGROUND OF THE INVENTION

Hearing aid devices and hearing devices generally comprise a housing, inwhich a microphone, an amplifier or amplifying device, a receiver, apower supply, mostly a zinc-air battery inter alia are arranged. Thereceiver is connected to an acoustic output of the housing, which emitsthe acoustic signals generated and prepared by the hearing aid deviceinto an auditory canal of a wearer of the hearing aid device.

In order to meet the aesthetic requirements of a wearer of the hearingaid device, this is to be as minimally externally visible on the weareras possible. These requirements are particularly high especially in thecase of hearing devices worn in the ear, referred to as in-ear hearingaid device. The components needed for an in-ear hearing aid device arethus to be designed as small as possible within the in-ear hearing aiddevice, to be packed as tightly as possible and to be reduced to aminimum.

Additionally, the components of the hearing aid device are to beshielded from external interferences for efficient functioning of thehearing aid device. Compensating elements such as coils, capacitors orcertain topology of conductive lines and cables may be arranged withinthe inner space of a housing of the hearing aid device to reduce theelectromagnetic interferences (EMI) within the housing. Alternatively, ashielding layer, such as having a gold plated layer on the inner surfaceof the hearing aid device may reduce the EMI within the housing of thehearing aid device. However, the use of compensating elements and theshielding layer may provide limitations on the miniaturization of thehearing aid device. Further, the manufacturing time of the hearing aiddevice is increased as the compensating elements are to be carefullypositioned into the hearing aid device or the gold plated layer is to beprovided onto the inner surface of the housing after the after has beenmade.

SUMMARY OF THE INVENTION

It is an object of the invention to provide shielding of components fromexternal electromagnetic interferences.

The above object is achieved by a hearing aid device and a method ofmanufacturing the hearing aid device, wherein the hearing aid devicecomprises a housing having a first non-conductive layer and a secondnon-conductive layer, and a first conductive layer between the firstnon-conductive layer and the second non-conductive layer.

The first conductive layer embedded in between the first non-conducivelayer and the second non-conducive layer of the housing of the hearingaid device shields an inner space of the housing from externalelectromagnetic interferences. The inner space of the housingaccommodates the electrical components therein. Further this facilitatesfurther miniaturization of the hearing aid device as the inner space ofthe housing may be used more efficiently and thus the hearing aid devicecan be more compact.

According to another embodiment, the hearing aid device furthercomprises a second conductive layer attached onto at least a portion ofthe inner surface of the second non-conductive layer. The secondconductive layer attached onto the inner surface of the secondnon-conductive layer of the housing of the hearing aid device enables inminiaturization of the hearing aid device. Additionally, the requirementof loose wires leads may be reduced and thus the electromagneticinterference within the housing of the hearing aid device is reduced.

According to yet another embodiment, the second conductive layer isconductively connected to an electrical component. Connecting anelectrical component to the second conductive layer enablesminiaturization of the hearing aid device and eliminates the requirementof loose wire leads.

According to yet another embodiment, the electrical component includes aprinted electrical component. Printed electrical components occupy lessspace and can easily be printed during the manufacturing of the housing.Thus, printed electrical components enable in miniaturization of thehearing aid device and also reduce the manufacturing time of the hearingaid device.

According to yet another embodiment, the first conductive layer and thesecond conductive layer are fabricated using a solid freeformfabrication technique selected from the group consisting of inkjetprinting, pneumatic spraying, screen printing, pad printing, laserprinting, dot matrix printing, thermal printing, lithography, and 3Dprinting. Fabricating or printing the first and the second conductivelayer using a solid freeform fabrication technique enables infabricating the first conductive layer between the first non-conducivelayer and the second non-conductive layer and the second conductive ontothe inner surface of the second non-conductive layer of the housing atthe time of the manufacturing of the housing.

According to yet another embodiment, the first conductive layer and thesecond conductive layer comprises an element from the group consistingof copper, gold, silver and electrically conductive polymer. Theseelements comprise enhanced conductive properties and therefore enablethe first conductive layer and the second conductive layer to have goodelectrical conductance.

According to yet another embodiment, the housing further comprises athird or additional non-conductive layer arranged inwardly of the firstnon-conductive layer and outwardly of the second non-conductive layer.Providing the third non-conductive layer enables providing additionalfeatures to the hearing aid device.

According to yet another embodiment, the hearing aid device furthercomprises a coil between the third non-conductive layer and the firstnon-conductive layer. The coil enables wireless communication with thehearing aid device. Additionally, the coil enables wireless charging ofthe hearing aid device. This enables efficient use of the inner space ofthe hearing aid device, and thus, enables miniaturization of the hearingaid device. Additionally, as the coil is provided external to the firstconductive layer, the inner space is shielded from any EMI arising outof the coil by the first conductive layer.

Another embodiment includes a method of manufacturing a hearing aiddevice, wherein the method comprises embedding a first conductive layerbetween a first non-conductive layer and a second non-conductive layerof a housing of the hearing aid device.

Embedding the first conductive layer between the first non-conductivelayer and the second non-conductive layer of the housing providesshielding of the inner space of the housing from EMI interferences.Further this facilitates further miniaturization of the hearing aiddevice as the inner space of the housing may be used more efficientlyand thus the hearing aid device can be more compact.

According to yet another embodiment, the embedding includes fabricatingthe first conductive layer between the first non-conductive layer andthe second non-conductive layer using a solid freeform techniqueselected from the group consisting of inkjet printing, pneumaticspraying, screen printing, pad printing, laser printing, dot matrixprinting, thermal printing, lithography, and 3D printing.

According to another embodiment, the method further comprises attachinga second conductive layer onto an inner surface of the secondnon-conductive layer. The second conductive layer attached onto theinner surface of the second non-conductive layer of the housing of thehearing aid device enables in miniaturization of the hearing aid device.Additionally, the requirement of loose wires leads may be reduced andthus the electromagnetic interference within the housing of the hearingaid device is reduced.

According to yet another embodiment, the second conductive layer isconductively connected to an electrical component.

According to yet another embodiment, wherein the electrical componentincludes a printed electrical component.

According to yet another embodiment, the method comprises embedding acoil between the first non-conductive layer and a third non-conductivelayer, the third non-conductive layer arranged inwardly of the firstnon-conductive layer and outwardly of the second non-conductive layer.

According to yet another embodiment, wherein the first conductive layer,the second conductive layer and the coil comprises an element from thegroup consisting of copper, silver, gold and electrically conductivepolymer.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described hereinafter with reference toillustrated embodiments shown in the accompanying drawings, in which:

FIG. 1 illustrates a cross sectional view of a housing of a hearing aiddevice according to an embodiment herein,

FIG. 2 illustrates a schematic block diagram of electrical componentsessential for a hearing aid function,

FIG. 3 illustrates a cross sectional view of housing comprising anadditional conductive layer according to an embodiment herein,

FIG. 4 a illustrates one example where two conductive layers areseparated by an insulating medium to form a positive and a negativecontact,

FIG. 4 b illustrates an insulating medium provided to act as a barrierbetween two additional conductive layers

FIG. 5 illustrates a pattern of attaching additional conductive layerson an inner surface of a second non-conductive layer of a housing of ahearing aid device according to an embodiment herein,

FIG. 6 illustrates another pattern of attaching additional conductivelayers on an inner surface of a second non-conductive layer of a housingof a hearing aid device according to an embodiment herein,

FIG. 7 illustrates connection of an electrical component to theadditional conductive layers according to an embodiment herein,

FIG. 8 illustrates connection between an electrical component andadditional conductive layers attached onto an inner surface of a secondnon-conductive layer in more detail,

FIG. 9 illustrates connection between an electrical component andadditional conductive layers using connection leads attached onto aninner surface of a second non-conductive layer according to anembodiment herein,

FIG. 10 a illustrates connection between an electrical component andconductive layers attached onto an inner surface of a housing of ahearing aid device using soft rings,

FIG. 10 b illustrates a soft ring in detail,

FIG. 11 a illustrates separation of a plurality of conductive layersusing insulating mediums in accordance to an embodiment herein,

FIG. 11 b is an enlarged side view of the encircled area of FIG. 11 a,

FIG. 12 a illustrates connection between two electrical components usingthe additional conductive layers attached onto an inner surface of asecond non-conductive layer of a housing of a hearing aid device andextended onto an outer surface of a casing of the electrical components,

FIG. 12 b additional conductive layers of FIG. 12 a,

FIG. 13 illustrates connection between an electrical component and anadditional conductive layer using a casing of an electrical component,

FIG. 14 illustrates a side view of a slot on an inner side of a housingof a hearing aid device according to an embodiment herein,

FIG. 15 is a cross sectional view of a housing of a hearing aid deviceillustrating a coil printed onto a layer of the hearing aid devicebetween a first non-conductive layer and a conductive layer according toan embodiment herein, and

FIGS. 16 a-16 c illustrate a method of manufacturing a housing of ahearing aid device according to an embodiment herein.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments are described with reference to the drawings,wherein like reference numerals are used to refer to like elementsthroughout. In the following description, for purpose of explanation,numerous specific details are set forth in order to provide a thoroughunderstanding of one or more embodiments. It may be evident that suchembodiments may be practiced without these specific details.

FIG. 1, illustrates a cross sectional view of a housing 10 of a hearingaid device 12 according to an embodiment herein. The housing 10comprises a conductive layer 18 between a first non-conductive layer 14and a second non-conductive layer 15. The conductive layer 18 with thefirst non-conductive layer 14 and the second non-conductive layer 15forms the wall of the housing 10. The conductive layer 18 providesshielding of an inner space 20 within the housing 10 fromelectromagnetic interference (EMI).

The hearing aid device 12 includes, but not limited to, in-ear hearingaid device, baby worn hearing aid device, behind the ear (BTE) hearingaid device, receiver in the canal (RIC) or ear hearing aid device, inthe canal (ITC) hearing aid device, mini canal (MIC) hearing aid device,completely in the canal (CIC) hearing aid device, extended wear hearingaid device, open fit hearing aid devices, eye glass hearing aid devicesand the like.

Still referring to FIG. 1, advantageously, the first non-conductivelayer 14 and the second non-conductive layer 15 are manufactured usingnon-conductive materials, for example a resin, an adhesive, a paint or asynthetic material, such that the first non-conductive layer 14 and thesecond non-conductive layer 15 do not exhibit any electrical conductanceproperty. The conductive layer 18 is manufactured using conductivematerials such that the conductive layer 18 is electrically conductive.

Preferably, the conductive layer 18 extends substantially at theinterior of the housing 10 between the first non-conductive layer 14 andthe second non-conductive layer 15. This provides efficient shielding ofthe inner space 20. In an implementation, the conductive layer 18 can bea thin foil. Advantageously, the conductive layer 18 may be embeddedbetween the first conductive layer 14 and the second conductive layer 15during the manufacturing of the housing 10. Alternatively, the housing10 may be manufactured such that the housing 10 comprises only theconductive layer 18 and the second non-conductive layer 15. However, itmay not be preferred to manufacture the housing 10 such that itcomprises only the conductive layer 18 and the second non-conductivelayer 15, as it may cause inconvenience to the user of the hearing aiddevice 12 because of the hardness of the conductive layer 18. Thehousing 10 having the conductive layer 18 between the firstnon-conductive layer 14 and the second conductive layer 15 shields theinner space 20 from EMI. Providing the conductive layer 18 between thefirst non-conductive layer 14 and the second non-conductive layer 15enables efficient usage of the inner space 20 of the housing 10.

Advantageously, the conductive layer 18 may be provided such that theconductive layer 18 encircles a substantial surface area of the secondnon-conductive layer 15. However, the conductive layer 18 may beprovided such that it encircles only a particular region or portion ofinterest of the second non-conductive layer 15.

FIG. 2 illustrates a schematic block diagram of electrical componentsessential for a hearing aid function. The hearing aid device 12comprises therein the electrical components essential for the hearingaid function, such as, a microphone 22, an amplifier 24, a receiver 26and a power source 28. The electrical component may also includeresistors, capacitors, coils and the like. The electrical componentssuch as the resistor, capacitor or the coil may also be printed usingsolid freeform fabrication techniques, such as a 3D printing technique.The hearing aid device 1 records ambient noise with the aid of themicrophone 22, amplifies these by means of the amplifier 24 and forwardsthem to the receiver 26. The power supply required for the amplifier 24for amplification is provided by the power source 28. The sound signalsfrom the receiver 26 are conveyed to the ear drum of the wearer by meansof an outlet canal, tube or wire.

Referring now to FIG. 1 and FIG. 2, the electrical components aretypically arranged in the inner space 20 of the housing 10. In anaspect, the conductive layer 18 shields the inner space 20 within thehousing 10 from EMI. This shields the electrical components arrangedwithin the inner space 20 from EMI.

FIG. 3 illustrates a cross sectional view of housing 10 comprising anadditional conductive layer according to an embodiment herein. Thehousing 10 of the hearing aid device 12 comprises therein the electricalcomponents essential for the functioning of the hearing aid device 12.In the shown example of FIG. 3, the housing 10 comprises the conductivelayer 18 between the first non-conductive layer 14 and the secondnon-conductive layer 15. In an aspect herein, an additional conductivelayer 21 may be attached onto the inner surface 16 of the secondnon-conductive layer 15 of the housing 10.

The conductive layer 21 is attached onto the inner surface 16 of thesecond non-conductive layer 15 of the housing 10 as the secondnon-conductive layer 15 is manufactured using a non-conductive material.The inner surface 16 of the second non-conductive layer 15 acts as asupport for the conductive layer 21.

In the shown example of FIG. 3, the additional conductive layer 21 mayrepresent a positive contact or a negative contact. However, multipleconductive layers may be attached onto the inner surface 16 of thesecond non-conductive layer 15. For example, if two conductive layersare attached the conductive layers may represent a positive and anegative contact. If multiple conductive layers are attached onto theinner surface 16 of the second non-conductive layer 15, the conductivelayers would have to be separated using an insulating medium.

FIG. 4 a illustrates one example where two conductive layers 21, 30 areseparated by an insulating medium 32 to form a positive and a negativecontact. The insulating medium 32 may be a non-conducting layer of theinner surface 16 of the second non-conductive layer 15 or an insulatinglayer attached between the conductive layers 21, 30. In certainembodiments, the insulating medium 32 may be an insulating layer suchthat the insulating layer acts as a barrier between the two additionalconductive layers 21, 30 as illustrated in FIG. 4 b.

FIG. 5 illustrates a pattern of attaching additional conductive layerson the inner surface of second non-conductive layer the housing of thehearing aid device according to an embodiment herein. In the shownexample of FIG. 5, a plurality of additional conductive layers 21, 30are attached on the inner surface 16 of FIG. 3 of the secondnon-conducive layer 15 of FIG. 3 in a stripe pattern. For example, oneof the additional conductive layers may represent a positive contact andthe other may represent a negative contact. For example, the additionalconductive layers 21 may represent a positive contact and the additionalconductive layers 30 may represent a negative contact. The additionalconductive layers 21 are separated from the additional conductive layers30 by an insulating medium 32. The insulating medium 32 in the presentembodiment is portions of the inner surface 16 of the secondnon-conducive layer 15 onto which no conductive layers 21, 30 areattached.

FIG. 6 illustrates another pattern of attaching additional conductivelayers on the inner surface of the housing of the hearing aid deviceaccording to an embodiment herein. In the shown example of FIG. 5, theadditional conductive layer 21 is attached on one half of the innersurface 16 of FIG. 3 of the second non-conductive layer 15 of FIG. 3 andthe conductive layer 30 is attached onto the other half of the innersurface 16 of the second non-conductive layer 15. The conductive layer21 is separated from the conductive layer 30 by an insulating medium 32.The insulating medium 32 in the present embodiment is portion of theinner surface 16 of the second non-conductive layer 15 onto which noconductive layers 21, 30 are attached.

Attaching multiple conductive layers enable, conductively connectingmultiple conductive layers to the electrical components. This enables inincreasing the fault tolerance of the hearing aid device 1 as redundantconnections to the electrical components can be made.

In the shown example of FIG. 3, the additional conductive layer 21extends over a substantial surface area of the inner surface 16 of thesecond non-conductive layer 15. However, the additional conductive layer21 may be attached onto only a portion of the inner surface 16 of thesecond non-conductive layer 21. If the additional conductive layer 21 isattached onto only a portion of the inner surface 16 of the secondnon-conductive layer 15, it may be required that the additionalconductive layer 21 is to be attached onto the inner surface 16 of thesecond non-conductive layer 15 such that the position of the additionalconductive layer 21 is suitable for making connections with electricalcomponents. If a single additional conductive layer is attached onto theinner surface 16 of the second non-conductive layer 15, the additionalconductive layer may extend over a substantial area of the inner surface16 of the second non-conductive layer 15. However, the additionalconductive layer can also extend over a portion or region of the surfaceof the inner surface 16 of the second non-conductive layer 15.

Referring now to FIG. 7, an electrical component, for example a receiver26 may be connected to the conductive layers 21, 30 using connectorleads 34, 36. The receiver 24 illustrated in FIG. 7 is shown as anexample and other electrical components may also be connected in asimilar manner. Other connector means, such as soft rings and the likemay also be used to connect an electrical component to the conductivelayers 21, 30. The connector leads 34, 36 may pierce into the respectiveconductive layers 21, 30. The connector leads 34, 34 enable suspendingthe receiver 9 rigidly and thus, reduce shocks and vibrationsencountered by the receiver due to the movement of the user of thehearing aid device. Additionally, the use of connector leads 34, 36enable to eliminate the requirement of soldering and thus, make themanufacturing process easy and less time consuming.

In an embodiment, multiple connections from the conductive layers 21, 30to the electrical component may be made to increase fault tolerance. Forexample, a plurality of connector leads 34, 36 may be used to make theconnections between the conductive layers 21, 30 and the electricalcomponent.

FIG. 8 illustrates connection between an electrical component andconductive layers attached onto the inner surface of the housingconnector leads in more detail. In the shown example of FIG. 8, areceiver 26 is connected to the conductive layers 21, 30 using connectorleads 34, 36. The connector leads 34, 36 may pierce into the conductivelayers 21, 30. The connector leads 34, 36 connect to a connection padand the connection pad in turn connects to the contact terminal of thereceiver 26. In the shown example of FIG. 6, the receiver 26 is held ina suspended position rigidly and thus reduces the chances of devicefailure due to shock and vibration. The multiple connector leads 34, 36enables in increasing fault tolerance of the hearing aid device 12 ofFIG. 7.

Referring again to FIG. 7, in an alternative implementation, the housing10 may be manufactured such that connector leads 34, 36 are attached tothe housing 10. The receiver 26 may be connected to the connector leads34, 36 and thus connect to the additional conductive layers 21, 30. FIG.9 illustrates connection between an electrical component and conductivelayers using connection leads attached onto the inner surface of thehousing. The receiver 26 is connected to the conductive layers 21, 30using connector leads 34, 36. The connector leads 34, 36 are attached tothe housing 10 of the hearing aid device 12 and are conductivelyconnected to the conductive layers 21, 30. The connector leads 34, 36may be attached to the housing 10 during fabrication of the housing 12.

Referring now to FIG. 7 and FIGS. 10 a through 10 b, in anotherimplementation soft ring 42 may be used to connect the receiver 26 tothe conductive layers 21, 30 and also to suspend the receiver 26rigidly. FIG. 10 a illustrates connection between an electricalcomponent and conductive layers attached onto the inner surface of thehousing of the hearing aid device using soft rings. In the shown exampleof FIG. 10 a, a receiver 26 is connected to the additional conductivelayers 21, 30 using soft rings 42. FIG. 10 b illustrates a soft ring 42in detail. The soft ring 42 comprises conductive medium 44 which areconnected to the additional conductive layers 21, 30 of FIG. 10 a. Theconductive mediums 44 connect to a connection pad 46 on the soft ring 42and the connection pad 44 connects to the contact terminal of thereceiver 26 of FIG. 10 a. The multiple conductive mediums 44 enablemultiple connections between the receiver 26 and the conductive layers21, 30. This increases the fault tolerance of the hearing aid device 12as redundant connections may be made to an electrical component. In theshown example of FIG. 10 a, the receiver 26 is held in a suspendedposition rigidly and thus reduces the chances of device failure due toshock and vibration.

Referring again to FIG. 7, another electrical component, for example, anamplifier 24 may be connected to the conductive layers 21, 30 usingconnector leads 38, 40. Soft rings 42 of FIG. 10 a and FIG. 10 b mayalso be used to connect the amplifier 24 to the conductive layers 21,30. Thus, connecting the receiver 26 and the amplifier 24 to theconductive layers 21, 30 enable conductively connecting the receiver 26to the amplifier 24 without the requirement of loose wire leads.Moreover, the connector leads 34, 36 hold the receiver 26 in a suspendedposition which is rigid and reduce shocks and vibrations encountered bythe receiver 26 due to the movement of the user of the hearing aiddevice. Suspending the receiver 26 inside the housing 10 eliminates theneed of extra caution to be taken while the hearing aid device is beingmanufactured. Alternatively, the manufacturing time for the hearing aiddevice 12 is reduced.

In an embodiment, a face plate 23 is provided at the distal end of thehearing aid device 12. Typically, the amplifier 24 is mounted onto theface plate 23. In an implementation, the face plate 22 and the amplifier24 may also be printed using the solid freeform techniques.

Still referring to FIG. 7, preferably, the additional conductive layers21, 30 are attached onto the inner surface 16 of the secondnon-conductive layer 15 by fabricating the housing 10 and the conductivelayers 21, 30. While fabricating the housing 22, the conductive layers21, may be fabricated onto the inner surface 16 of the secondnon-conductive layer 15. In certain implementation additionalnon-conductive layers of the housing 10 may be fabricated onto the innersurface 16 to which the conductive layers 18, 30 are fabricated.Additional non-conductive layers of the housing 10 may be fabricated forfabricating multiple layers of additional conductive layers or forproviding insulation as the housing 10 is manufactured using anon-conducting material.

Multiple additional conductive layers one above the other may also beprovided. Advantageously, one additional conductive layer may beseparated from another by an insulating medium. Alternatively aninsulating layer may be attached onto the inner surface 16 of the secondnon-conductive layer 15 to separate two additional conductive layers. Inan example, if the additional conductive layers are conductive pathways,the point of intersection of two additional conductive layers may beseparated by having an insulating layer therein. FIG. 11 a illustratesseparation of a plurality of additional conductive layers usinginsulating mediums. A plurality of additional conductive layers 21 athrough 21 e are separated from each other using insulating mediums 32 athrough 32 f respectively. In the example of FIG. 11 b, an enlarged sideview of the encircled area of FIG. 11 a is shown. It is seen that theadditional conductive layers 21 a and 21 b are separated by theinsulating medium 32 a. The insulating medium 32 a enables to preventconduction between the additional conductive layers 21 a and 21 b. Thus,multiple additional conductive layers may be printed by havingrespective insulating mediums between them.

Referring now to FIG. 11 a and FIG. 11 b, in an implementation theconductive layers 21 a through 21 e may be filaments and the point ofintersections can be separated by having insulating mediums 32 a through32 f therein.

In another embodiment, the electrical components may be fixedlypositioned onto the inner surface comprising the conductive layers. Theconductive layers may be extended onto the outer surface of a casing ofthe electrical component and thus complete the connection. FIG. 12 aillustrates connection between two electrical components using theadditional conductive layers attached onto the inner surface of thesecond non-conductive layer of the housing of the hearing aid device andextended onto an the outer surface of the casing. In the shown exampleof FIG. 12 a, electrical components, for example, a receiver 26 and anamplifier 24 may be held fixedly onto the inner surface 16 of the secondnon-conductive layer 15. The conductive layers 21, 30 may be printedonto the inner surface 16 of the second non-conductive layer 15 and ontothe outer surface 48 of the casing 50 of the receiver 26 and theamplifier 24 to connect the receiver 26 and the amplifier 24.Alternatively, the additional conductive layers 21, 30 may beconductively connected to a single electrical component to provide powerto the electrical component. The conductive layers 21, 30 printed ontothe outer surface 48 of the casing 50 make contact with connection pads52 to connect the receiver 26 to the conductive layers 21, 30. Aninsulating medium 32 may be provided between the conductive layers 21,30 for separating the conductive layers 21, 30. Preferably, theinsulating medium 32 is provided at the point of intersection of theconductive layers 21, 30. However, the insulating medium 32 may beprovided over the entire surface also. Preferably, in the presentembodiment, the conductive layers 21, 30 are conductive pathways printedonto the inner surface 16 of the second non-conductive layer 15 and theouter surface 48 of the casing 50 of the receiver 26.

FIG. 12 b illustrates a side view of the connection between theelectrical components using the conductive layers of FIG. 12 a. In theexample of FIG. 12 b, only the conductive layer 21 is illustrated forunderstanding purposes. It is seen that the conductive layer 21 isprinted onto the inner surface 16 and over the outer surface 48 of thecasing 50 of the amplifier 24 and the receiver 26. The presentembodiment provides the advantage of connecting an electrical componentto the conductive layers 21, 30 by printing the conductive layers 21, 30on the outer surface 48 of the casing 50 of the electrical component.

FIG. 13 illustrates connection between an electrical component and aconductive layer using a casing of the electrical component. Preferably,the conductive layer 21 extends over a substantial surface area of theinner surface 16 of the second non-conductive layer 15. However, theconductive layer 21 may extend over only a particular portion or regionof the inner surface 16. In the present example, the conductive layer 21may be adapted to operate either as a positive contact or a negativecontact. The electrical component, for example the receiver 26 comprisesa casing 53 having a conductive outer surface 54. The receiver 26 isfixedly positioned onto the conductive layer 21 attached onto the innersurface 16 such that the outer surface 54 of the casing 53 of thereceiver 26 is in contact with the conductive layer 21. The receiver 26is shown for the purposes of illustration only and other electricalcomponents may also be positioned onto the conductive layer 21.Internally, the outer surface 54 of the casing 53 may be connected to aconnection point so that the outer surface 54 of the casing 53 isconnected to the internal circuitry of the electrical component, i.e.,the receiver 26. In an alternative embodiment, the casing 53 may be madeusing a conductive material such that the outer surface 54 and an innersurface of the casing 53 are conductive. In an implementation, only aportion of the outer surface 54 of the casing 53 may be conductive. Ifonly a portion of the outer surface 54 of the casing 53 is conductive,it may be required that the receiver 26 be positioned onto theconductive layer 21 such that the conductive portion of the outersurface 54 of the casing 53 in is contact with the conductive layer 21.Accordingly, the electrical component may be conductively connected tothe conductive layer 21. Additionally, one electrical component may beconductively connected to another electrical component using theconductive layer 21.

For an example, the conductive layer 21 may be adapted to operate as acommon ground and the outer surface 54 of the casing 53 may be connectedto the conductive layer 21 to connect the electrical component to theground. Alternatively, the conductive layer 21 may be adapted to operateas a positive contact and the outer surface 54 of the casing 53 may beconnected to the conductive layer 21 to connect the electrical componentto a positive contact.

In an embodiment, the housing 22 may comprise a slot to receive anelectrical component, for example the receiver 26. FIG. 14 illustrates aside view of a slot 55 on the inner side 56 of the housing 10. The slot55 is provided on the inner side 56 of the housing 10. The electricalcomponent when positioned into the slot 55 is conductively connected tothe conductive layer 21. The conductive layer 21 may be attached onto asubstantial area of the inner surface 16 of the second non-conductivelayer 15, including the slot 55. Alternatively, the conductive layer 21may be attached onto a portion of the inner surface 16 only within theslot 55.

This enables in reducing the requirement of loose wire leads and thusreduces the electromagnetic interference within the hearing aid device.Additionally, as there is no requirement of soldering, the manufacturingtime is reduced and also there is possibility of miniaturizing thehearing aid device as the area covered by a soldering point issubstantially large.

FIG. 15 is a cross sectional view of the housing of the hearing aiddevice illustrating a coil provided on the first non-conductive layer.In the shown example of FIG. 15, a coil 58 is provided on the firstnon-conductive layer 14 of the housing 10. Typically, the coil 58comprises a structure of a helix and spirals around the non-conductivelayer 14 of the housing 10. The housing 10 may comprises an additionalnon-conductive layer 60 over the coil 58. The additional non-conductivelayer 60 prevents the coil 58 from being damaged and also preventsinconvenience to the user of the hearing aid device 12 due to thepresence of the coil 58.

The coil 58 may be used for wireless communication or for wirelesscharging of the hearing aid device 12. This enables efficient use of theinner space 20 of FIG. 1 of the hearing aid device 12, and thus, enablesminiaturization of the hearing aid device 12. Additionally, as the coil58 is provided external to the first conductive layer 18, the innerspace 20 is shielded from any EMI arising out of the coil 58 by thefirst conductive layer 18.

Referring now to FIG. 1 through FIG. 15, the housing 10 of the hearingaid device 12 is manufactured by embedding the first conductive layer 18between the first non-conductive layer 14 and the second non-conductivelayer 15. Advantageously, the conductive layer 18 is embedded betweenthe first non-conductive layer 14 and the second non-conductive layer 15using a solid freeform fabrication technique. The solid freeformfabrication technique includes, but not limited to inkjet printing,pneumatic spraying, screen printing, pad printing, laser printing, dotmatrix printing, thermal printing, lithography, and 3D printing. Solidfreeform fabrication technique provides the advantages of enabling themanufacturing of the first conductive layer 18, the first non-conductivelayer 14 and the second non-conductive layer 15 simultaneously such thatthe housing 22 comprises the first conductive layer 18 between the firstnon-conductive layer 14 and the second non-conductive layer 15. Thisdecreases the manufacturing time of the hearing aid device 1 and alsoreduces the complexities. Moreover, using solid freeform fabricationtechnique to manufacture the housing 10 eliminates the requirement forhaving separate moulds for individual hearing aid device 12 design.However, the housing 10 may be manufactured using other manufacturingtechniques such as MID and inset molding. If the hearing aid device ismanufactured using a MID or an inset molding technique, a mould may berequired to be created for each hearing aid device. Additionally, themanufacturing time of the hearing aid device 12 may be increased as theconductive layer 18, the first non-conductive layer 14 and the secondnon-conductive layer 15 will have to be manufactured one at a time.

In a preferred embodiment, the housing 10 is fabricated a 3D printingtechnology. Solid freeform fabrication techniques, such as the 3Dprinting technology enables fabricating a product using multiplematerials. For example, a first printer head may print the firstnon-conductive layer 14 of the housing, a second printer head may printthe conductive layer 18 and a third printer head may print the secondnon-conductive layer 15. The first printer head may be used to print thesecond non-conductive layer 15 as typically, the first conductive layer14 and the second conductive layer 15 comprises the same non-conductingmaterials. The printing is done by fabricating layers one after the nextsuccessively in physical space until the model or the product iscompleted.

For example, the conductive layer 18, the first conductive layer 18, thefirst non-conductive layer 14 and the second non-conductive layer 15 maybe printed by the respective printer heads by dispersion of suitablerespective printing compositions. The printing composition for printingthe non-conductive layers 14, 15 may comprise particles ofnon-conducting elements, for example a resin. The printing compositionfor printing the conductive layer 18 may comprise particles ofconductive elements, such as copper, gold, silver, electricallyconductive polymer, and the like. The respective printing compositionsfor printing the non-conductive layers 14, 15 and the conductive layer18 may comprise nanoparticles of elements suitable for printing therespective layers. The conductive layer 21 may be printed onto the innersurface 16 of the second non-conductive layer 15 in a similar manner.Also the coil 58 and the additional non-conductive layer 60 may beprinted in a similar manner.

Solid freeform fabrication techniques, such as the 3D printingtechnology enables fabricating a product using multiple materials. Itwill be apparent to a person skilled in the art that the layers of thehousing 10 and the conductive layer 18 may be printed simultaneouslyusing freeform fabrication techniques using the respective printingheads such that the end product is the housing 10 having the conductivelayer 18 between the first non-conducive layer 14 and the secondnon-conductive layer 15.

FIGS. 16 a through 16 c illustrate a method of manufacturing a housingof a hearing aid device according to an embodiment herein. Referring nowto FIG. 16 a a first non-conductive layer 14 of the housing 10 of FIG. 1is printed. The first non-conductive layer 14 comprises an inner surface66 and an outer surface. Next, as illustrated in FIG. 16 b, a conductivelayer 18 is printed onto the inner surface 66 of the firstnon-conductive layer 14. The conductive layer 18 comprises an innersurface 68. In FIG. 16 c, a second non-conductive layer 15 is printedonto an inner surface 68 of FIG. 16 b of the conductive layer 18. Thusthe conductive layer 18 is positioned between the first non-conductivelayer 14 and the second non-conductive layer 15.

Thus, the conductive layer 18 is embedded between the firstnon-conductive layer 14 and the second non-conductive layer 15 of thehousing 10.

The embodiments described herein provide a shielding layer for shieldingthe inner space of the hearing aid device from EMI. The inner space ofthe hearing aid device accommodates electrical components essential forthe hearing aid function. Moreover, this enables efficient use of theinner space of the housing and thus enables the design of the hearingaid device to me more compact. Additionally, the requirement of loosewire leads to connect electrical components of a hearing aid device maybe eliminated. Moreover, the manufacturing time of the hearing aiddevice is reduced. Eliminating the need of loose wire leads also enablesthe electronic component to be inserted independently into the housingduring manufacturing of the hearing aid device, and thus eliminating theextra caution required during manufacturing. Moreover, certainembodiments provide a means to suspend the receiver rigidly so that thepossibility of the failure of the hearing aid device is reduced.Suspension of the receiver independently enables the receiver to bepushed into position and thus enable easy repairing of the hearing aiddevice. Additionally, the elimination of loose wire leads enable inreducing the electromagnetic interference within the hearing aid device.Militarization of the hearing aid device is also possible as therequirement of soldering is eliminated.

While this invention has been described in detail with reference tocertain preferred embodiments, it should be appreciated that the presentinvention is not limited to those precise embodiments. Rather, in viewof the present disclosure which describes the current best mode forpracticing the invention, many modifications and variations wouldpresent themselves, to those of skill in the art without departing fromthe scope and spirit of this invention. The scope of the invention is,therefore, indicated by the following claims rather than by theforegoing description. All changes, modifications, and variations comingwithin the meaning and range of equivalency of the claims are to beconsidered within their scope.

LIST OF REFERENCE SIGNS

-   -   10 Housing    -   12 Hearing aid device    -   14 First non-conductive layer    -   15 Second non-conductive layer    -   15 Inner surface    -   18 Conductive layer    -   20 Inner space    -   21 30 Additional conductive layers    -   22 Microphone    -   23 Face plate    -   24 Amplifier    -   26 Receiver    -   28 Power source    -   32 Insulating medium    -   34 36 Connector leads    -   38 40 Connector leads    -   42 Soft ring    -   44 Conductive medium    -   46 Connection pad    -   48 Outer surface of the casing 50    -   50 Casing    -   52 Connection pad    -   53 Casing    -   54 Outer surface of the casing 53    -   55 Slot    -   56 Inner side    -   58 Coil    -   60 Third non-conductive layer    -   66 Inner surface of the first non-conductive layer 15    -   68 Inner surface of the conductive layer 18

The invention claimed is:
 1. A hearing aid device, comprising: a housingincluding a first non-conductive layer, a second non-conductive layer,and a third non-conductive layer, said second non-conductive layerhaving an inner surface, said third non-conductive layer disposedinwardly of said first non-conductive layer and outwardly of said secondnon-conductive layer; a coil disposed and embedded between said thirdnon-conductive layer and said first non-conductive layer; a firstconductive layer disposed between said first non-conductive layer andsaid second non-conductive layer; a second conductive layer attachedonto a portion of said inner surface of said second non-conductivelayer; and said inner surface of said second non-conductive layer actingas a support for said second conductive layer.
 2. The hearing aid deviceaccording to claim 1, which further comprises an electrical component towhich said second conductive layer is conductively connected.
 3. Thehearing aid device according to claim 2, wherein said electricalcomponent is a printed electrical component.
 4. The hearing aid deviceaccording to claim 1, wherein said first conductive layer and saidsecond conductive layer are solid freeform fabricated layers selectedfrom the group consisting of: an inkjet printed layer, a pneumaticsprayed layer, a screen printed layer, a pad printed layer, a laserprinted layer, a dot matrix printed layer, a thermal printed layer, alithographic layer, and a 3D printed layer.
 5. The hearing aid deviceaccording to claim 1, wherein said first conductive layer and saidsecond conductive layer include an element selected from the groupconsisting of: copper, gold, silver, and electrically conductivepolymer.
 6. A method for manufacturing a hearing aid device, the methodcomprising the following steps: producing a housing of the hearing aiddevice having a first non-conductive layer, a second non-conductivelayer, and a third non-conductive layer disposed inwardly of the firstnon-conductive layer and outwardly of the first non-conductive layer;embedding a coil between the first non-conductive layer and the thirdnon-conductive layer; embedding a first conductive layer between thefirst non-conductive layer and the second non-conductive layer;attaching a second conductive layer onto an inner surface of the secondnon-conductive layer; and supporting the second conductive layer on theinner surface of the second non-conductive layer.
 7. The methodaccording to claim 6, which further comprises embedding the firstconductive layer between the first non-conductive layer and the secondnon-conductive layer by a solid freeform technique selected from thegroup consisting of: inkjet printing, pneumatic spraying, screenprinting, pad printing, laser printing, dot matrix printing, thermalprinting, lithography, and 3D printing.
 8. The method according to claim6, which further comprises conductively connecting an electricalcomponent to the second conductive layer.
 9. The method according toclaim 8, which further comprises providing the electrical component as aprinted electrical component.
 10. The method according to claim 6, whichfurther comprises including in the first conductive layer, the secondconductive layer and the coil an element selected from the groupconsisting of: copper, gold, silver, and electrically conductivepolymer.
 11. The hearing aid device according to claim 1, wherein saidsecond conductive layer extends over a substantial surface area of saidinner surface of said second non-conductive layer.
 12. The methodaccording to claim 6, wherein the second conductive layer extends over asubstantial surface area of the inner surface of the secondnon-conductive layer.